An active volcano is one that is erupting or could erupt again – either currently active (Etna, Stromboli, Iceland’s Reykjanes) or dormant but capable of reawakening (Vesuvius, Teide, Elbrus). A dormant volcano is quiet now but not considered dead; it is monitored because it has erupted in the geologically recent past. An extinct volcano is not expected to erupt again. In practice, most of the famous European volcanoes people visit are active or dormant-and-monitored, which is exactly why official alert levels and certified guides matter so much.

Iceland sits on the Mid-Atlantic Ridge, where the Eurasian and North American plates pull apart about 2.5 cm a year, making it Europe’s most volcanically active country. The Reykjanes Peninsula, in the southwest near Reykjavik, entered an eruptive phase in March 2021 when Fagradalsfjall erupted for the first time in roughly 800 years. Since late 2023, a series of eruptions along the Sundhnukur crater row has repeatedly forced evacuations of the town of Grindavik and threatened the Blue Lagoon.

The most recent eruption in the series ended in August 2025. As of 2026, the Icelandic Met Office reports that more magma has accumulated beneath the area than at any earlier point in the sequence, and scientists consider another eruption likely in the coming weeks or months, somewhere along the same stretch north of Grindavik. Volcanologists suggest this phase could continue for years or even decades.

Mount Etna – Europe’s most active volcano3,357 m · Sicily · Very active · above ~3 million people

Etna is the tallest active volcano in continental Europe and among the most active on Earth, with frequent summit paroxysms that throw ash and lava fountains high above Sicily. Its lower flanks are densely populated, home to roughly three million people, and eruptions regularly disrupt Catania’s airport with ash. For visitors, the lower slopes are freely walkable, while the summit craters require a certified guide and depend on the day’s activity and alert level.

Stromboli – the constant one924 m · Aeolian Islands · Constantly active

Stromboli has been in near-continuous mild eruption for over two millennia – so regular that its steady, rhythmic explosions gave their name to “Strombolian” eruptions worldwide. Guided evening hikes time the ascent so climbers watch glowing lava arc against the night sky above the Sciara del Fuoco, the scar down which material tumbles to the sea. It also produces occasional larger, more dangerous paroxysms, which is why access levels are tied to the current alert and guides are mandatory above a certain height.

Campi Flegrei – the “Phlegraean Fields” – is Europe’s largest active caldera, a sprawling volcanic system beneath the western suburbs of Naples and the town of Pozzuoli, with roughly half a million people living inside it. Unlike a single cone, it is a collapsed crater with many vents, and it has been in a phase of accelerating unrest since 2005: total ground uplift of more than a metre, recent uplift around 10 mm a month, frequent earthquake swarms (about 70 quakes in a single week in February 2026), and rising volcanic gas emissions. Its last actual eruption was in 1538, when Monte Nuovo – a new 133-metre hill – grew out of flat ground in about eight days.

Vesuvius, 20 km to the east, is the famous stratovolcano that buried Pompeii in AD 79. It last erupted in 1944 and is currently quiet, but it is far from dead: it too is continuously monitored by INGV, with a defined “red zone” evacuation plan for the roughly 700,000 people who live close to it. You can walk its crater-rim trail year-round – see our Vesuvius climb guide.

Visiting Europe’s active volcanoes is safe and hugely popular for most people, but it depends entirely on respecting the monitoring. The core rules: go only when the official alert level allows access; use certified local guides on anything active; stay on approved routes and behind every rope-off zone; carry the right gear (sturdy footwear, wind and gas protection where advised); and check the status the same day, because access can change within hours. Volcano-specific hazards – toxic gas that pools in low ground, sudden explosions with little warning, unstable lava terrain, and extreme heat near active vents – are why local guidance is not optional.